The invention relates to cogranulates comprising alkali metal phyllosilicates and disintegrants and to the use thereof in detergents and cleaners in tablet form.
WO 95/21908 has already disclosed tablets for use in detergents and cleaners, which are obtained by compressing a mixture consisting essentially of phyllosilicates and organic disintegrants, such as, for example, cellulose or cellulose derivatives. Both components are in powder form.
WO 98/40462 describes compacts which comprise cellulosic material in granulate form, and WO 98/40463 describes tablets which comprise cellulose-containing granulates and other constituents. These other constituents, which also include crystalline and amorphous silicates, can likewise be in the form of a granulate, although in each case the cellulose-containing granulate is free from silicates.
We have now found that cogranulates comprising alkali metal phyllosilicates and a disintegrant can be used advantageously for the disintegration of tablets for detergents and cleaners.
The invention provides cogranulates comprising alkali metal phyllosilicates and disintegrants.
Preferred alkali metal phyllosilicates which can be used advantageously in the cogranulates according to the invention are those of the formula NaMSixO2x+1xc2x7yH2O, where M is sodium or hydrogen, x is a number from 1.9 to 4, and y is a number from 0 to 20, and preferred values for x are 2, 3 or 4. Such phyllosilicates are described in EP-B-0 164 514, to which reference is expressly made here. Preferred phyllosilicates are those in which M is sodium, and x assumes the values 2 or 3. In particular, both beta- and delta-sodium disilicates Na2Si2O5xc2x7yH2O are preferred, it being possible to obtain beta-sodium disilicate, for example, by the process described in WO-A-91/08171. Beta-sodium disilicate is available commercially under the name SKS 7, and delta-sodium disilicate is available commercially under the name SKS 6 (commercial products from Clariant GmbH).
Further phyllosilicates which can be used preferentially for the cogranulate according to the invention are described in DE-A-198 30 591.5. This is a finely divided crystalline layered sodium disilicate of the formula NaMSixO2x+1. yH2O, where M is sodium or hydrogen, x is a number from 1.9 to 4 and y is a number from 0 to 20, which is notable for the fact that it has a content of from 0 to 40% by weight of alpha-disodium silicate, 0 to 40% by weight of beta-disodium disilicate, 40 to 100% by weight of delta-dinatrium disilicate and 0 to 40% by weight of amorphous fractions, and a screen oversize residue of less than 60%, and is free from sodium metasilicate.
DE-A-196 01 063 describes a crystalline sodium phyllosilicate of the formula xNa2O*ySiO2*zP2O5 with an x:y ratio of from 0.35 to 0.6, an x:z ratio of from 1.75 to 1200 and a y:z ratio of from 4 to 2800. These phosphorus-containing phyllosilicates, which have a high degree of crystallinity and a very high calcium-binding capacity, are likewise preferably used for the cogranulate according to the invention.
Also used according to the invention are crystalline alkali metal phyllosilicates of the formula a MI2O * b EO2 * c X2O5 * d ZO3xc2x7SiO2 * e H2O, in which MI is an alkali metal, E is an element from the fourth main group, X is an element from the fifth main group and Z is an element from the sixth main group of the Periodic Table of the Elements, and where the following apply:
0.25xe2x89xa6axe2x89xa66.25
2.5xc2x710xe2x88x924xe2x89xa6bxe2x89xa65.63
0xe2x89xa6cxe2x89xa62.81
0xe2x89xa6dxe2x89xa65.63
0xe2x89xa6exe2x89xa615.3
In this connection, preferred crystalline alkali metal phyllosilicates are those which have a certain content of phosphorus, sulfur and/or carbon.
Suitable silicates are, however, also highly alkaline crystalline sodium silicates of the composition.
All following percentages refer to percentages by weight, unless otherwise stated.
Na2O * x SiO2* y H2O
where x is a number between 1.2 and 2.1, and y is a number between 0 and 20, and the highly alkaline crystalline sodium silicate consists of 70 to 98% by weight of layered disodium disilicates and 2 to 30% by weight of non-phyllosiliceous sodium silicates of the formula
Na2O*v SiO2*w H2O
in which v is a number between 0.05 and 2, and w is a number between 0 and 20.
Finally, preference is also given to using sparingly soluble alkali metal silicates which are notable for the fact that they comprise alkali metal phyllosilicates in finely dispersed form in a non-phyllosiliceous alkali metal silicate environment of the formula x MI2Oxc2x7y SiO2, in which M1 is an alkali metal and y/x is (1.9 to 500): 1. In this connection, the alkali metal silicate corresponds overall to the formula
a MI2Oxc2x7b MIIOxc2x7c X2O3xc2x7d Z2O5xc2x7e SiO2xc2x7f H2O
in which MI is an alkali metal, MII is an alkaline earth metal, X is an element from the third main group and Z is an element from the fifth main group of the Periodic Table of the Elements and where the following apply:
0xe2x89xa6axe2x89xa61;
0xe2x89xa6bxe2x89xa60.5;
0xe2x89xa6c/exe2x89xa60.05;
0xe2x89xa6d/exe2x89xa60.25;
1.9xe2x89xa6exe2x89xa64;
0xe2x89xa6ffxe2x89xa620
Preference is given here to sparingly soluble alkali metal silicates which have a certain content of alkaline earth metal ions (magnesium and/or calcium), boron and/or phosphorus.
Suitable disintegrants are, in particular, starch and starch derivatives, cellulose and cellulose derivatives, for example microcrystalline cellulose, CMC MC, alginic acid and salts thereof, carboxymethylamylopectin, polyacrylic acid, polyvinylpyrrolidone and polyvinylpolypyrrolidone. Particular preference is given to the use of cellulose in the form of compacted pulp, such as TMP (thermomechanical pulp) or CTMP (chemothermomechanical pulp). Such products are available, for example, under the type designations Arbocel(copyright)-B and Arbocel(copyright)-BC (beechwood cellulose), Arbocel(copyright)-BE (beechwood sulfite cellulose), Arbocel(copyright)-B-SCH (cotton cellulose), Arbocel(copyright)-FIC (spruce cellulose) and other Arbocel(copyright) grades (Arbocel(copyright)-TF-30-HG) from Rettenmaier. Particular preference is given to those celluloses which have an average fiber length to diameter ratio of 16 to 1, preferably 10 to 4. Such products are available under the name Arbocel(copyright) TIC 200 and Arbocel(copyright) FDY 600 from Rettenmaier. Also preferred are microcrystalline celluloses, such as, for example, the Hewetten(copyright) grades (e.g. Heweften 200) and Vivapur grades (e.g. Vivapur 200).
The cogranulate preferably consists of 1 to 30% of disintegrants and 70 to 99% of alkali metal phyllosilicate. Particular preference is given to lower cellulose contents, especially between 5 and 19%. As further ingredients, the cogranulates can comprise between and 1 and 30% of granulation auxiliaries and phlegmatizers and also additional disintegration-promoting components.
Granulation auxiliaries and phlegmatizers are water, water glass, polyethylene glycol, nonionic surfactants, anionic surfactants, polycarboxylate copolymer, glycerol or ethylene glycol.
Disintegration-promoting components are readily soluble materials, generally alkali metal carbonates, alkali metal hydrogencarbonates, alkali metal silicates, alkali metal sulfates, alkali metal hydrogensulfates, alkali metal halides, alkali metal phosphates, alkali metal dihydrogenphosphates, alkali metal hydrogenphosphates, alkali metal borates, organic acids and salts thereof (citrates, acetates, formates, ascorbates etc.) or readily soluble organic compounds (e.g. urea). Readily soluble materials help to maintain or increase the porosity during the disintegration phase of the tablet. Preference is given to substances which form water of hydration, particular preference to those whose crystal lattice expands as a result of the incorporation of water of crystallization.
Swelling materials, such as, for example, smectites, polyvinylpyrrolidones, starches, can also be used as the disintegration-promoting component.
Suitable disintegration-promoting components are also substances which react with one another or with water with the evolution of gas. Preference is given here to combinations of solid acid and salt of an acid which is unstable (in water). Particular preference is given to soda and citric acid and sodium hydrogencarbonate and citric acid.
Likewise suitable for this purpose are also substances which liberate oxygen as a result of thermal, catalytic or enzymatic decomposition, e.g. inorganic and/or organic peroxides, and substances which react with water itself with the evolution of gas: e.g. peroxides, gas hydrates and salts which comprise occluded gases.
The cogranulate according to the invention preferably has a fines fraction of more than 2% by weight, particularly preferably more than 5% by weight, and preferably a 500 to 1500 xcexcm fraction of more than 60% by weight and particularly preferably more than 70%.
The cogranulate according to the invention is prepared by firstly mixing phyllosilicates and disintegrants. If necessary, a granulation auxiliary or phlegmatizer can be added. The material is then compacted by compression granulation, and processed by grinding and screening.
The compression granulation is carried out by roll compaction, briquetting etc. In the case of roll compaction, a compaction pressure of from 1 kN/cm to 30 kN/cm is preferred and a compaction pressure of from 2 kN/cm to 20 kN/cm is particularly preferred.
For the grinding of the compacted raw material, ball mills, pendulum roller mills, roller mills, compressed-air mills, hammer mills and impact mills are suitable. If desired, grinding auxiliaries can be add ed.
The cogranulates according to the invention can be used in detergents and cleaners. Preference is given here to tablet-shaped heavy duty detergents, color detergents, specialty detergents and machine dishwashing detergents. Heavy duty detergents are balanced formulations with the aim of as high a detergency as possible. Color detergents are intended primarily to protect colored textiles with regard to bleaching and fading of the colors and matting of the fibers. Specialty detergents are aimed at narrow areas of application, such as stain-removal salts, curtain detergents, wool detergents and commercial laundry etc.
Machine dishwashing detergents serve for the domestic or commercial cleaning of crockery, cutlery etc.
The content of cogranulate in the detergents and cleaners can vary depending on the intended use. An effective cellulose amount of from 1 to 15%, particularly preferably from 4 to 10%, based on the total amount of detergent and cleaner, is preferred. This can be achieved by cogranulate amounts of from 3 to 95%, particularly preferably 13 to 70%.
Builder combinations are frequently used in detergents and cleaners. Preference is given here to 3 to 95% of phyllosilicate/disintegrant cogranulate and 0.5 to 70% of cobuilder. Cobuilders are crystalline aluminosilicates and/or monomeric carboxylic acids and salts thereof and/or oligomeric polycarboxylic acids and salts thereof and/or polymeric carboxylic acids and salts thereof and/or alkali metal carbonates and/or alkali metal hydrogencarbonates and/or crystalline alkali metal silicates having a crystal lattice without a layer structure and/or X-ray amorphous alkali metal silicates.
It is also possible to use phyllosilicates either in the cogranulate or also additionally separate therefrom. 3 to 95% of phyllosilicate/disintegrant cogranulate and 0.5 to 70% of additional phyllosilicate are likewise preferred. Particular preference is given to detergents and cleaners likewise comprising 3 to 95% of phyllosilicatelcellulose cogranulate and 0.5 to 70% of cobuilder and 0.5 to 70% of additional phyllosilicate.
Moreover, detergents and cleaners comprise a plurality of surfactants which can be nonionic, anionic, cationic or zwitterionic in nature. Of the nonionic surfactants, the alkyl ethoxylates are important. Surprisingly, it has been found that particularly those based on C11-oxo alcohols and methyl ester ethoxylates have a favorable effect on tablet disintegration. In the case of the methyl ester ethoxylates, C12-14-alkyl derivatives having 8 EO units and C8-10-alkyl derivatives having 10 EO units are particularly preferred.
Preference is given to detergents and cleaners comprising 3 to 95% of phyllosilicate/disintegrant cogranulate and 0.5 to 60% of surfactant, in particular those formulations which comprise 3 to 95% of phylosilicate/cellulose cogranulate and 0.5 to 60% of surfactant and 0.5 to 70% of additional phyllosilicate.
In detergents and cleaners, bleaching-active substances serve to destroy and reduce germs and remove stains. Bleaching-active substances are, for example, perborates, percarbonates, persulfates, organic peroxides, enzymes, bleaching catalysts bas ed on heavy metals etc.
Preference is given to the following ratios: 3 to 95% of phyllosilicates/disintegrant cogranulate and 0.5 to 60% of bleaching-active substances; likewise preferred are the ratios: 3 to 95% of phyllosilicate/cellulose cogranulate and 0.5 to 60% of bleaching-active substances and 0.5 to 70% of additional phyllosilicate.
Detergents and cleaners of the following compositions are also preferred:
1) 3 to 95% of phyllosilicate/disintegrant cogranulate and 0.5 to 70% of cobuilder and 0.5 to 60% of surfactant;
2) 3 to 95% of phyllosilicate/disintegrant cogranulate and 0.5 to 70% of cobuilder and 0.5 to 60% of surfactant and 0.5 to 70% of phyllosilicate;
3) 3 to 95% of phyllosilicate/disintegrant cogranulate and 0.5 to 70% of cobuilder and 0.5 to 60% of bleaching-active substances;
4) 3 to 95% of phyllosilicate/disintegrant cogranulate and 0.5 to 70% of cobuilder, 0.5 to 60% bleaching-active substances and 0.5 to 70% of phyllosilicate;
5) 3 to 95% of phyllosilicate/disintegrant cogranulate and 0.5 to 70% of cobuilder and 0.5 to 60% of surfactant and 0.5 to 60% of bleaching-active substances;
6) 3 to 95% of phyllosilicate/disintegrant cogranulate and 0.5 to 70% of cobuilder and 0.5 to 60% of surfactant and 0.5 to 60% of bleaching-active substances and 0.5 to 70% of phyllosilicate.
It is also possible to color the cogranulate. Preferred concentration ranges are 50 to 99% of phyllosilicate/disintegrant cogranulate and 0.01 to 10% of dye/pigment. Suitable dyes may primarily be the Sandolan types (Sandolan Walkblau N-BL 150) or also Telon types (Telon Blau AFN, DyStar). Pigments such as Patentblau (DyStar) can also be used.
The detergents and cleaners which comprise the cogranulates according to the invention can be in the form of powders or tablets. For the tableting of the detergents, compaction pressures of from 0.08 to 3.8 kN/cm2 are preferred, and of 0.5 to 2.3 kN/cm2 are particularly preferred.
For the tableting of the machine dishwashing detergents, compaction pressures of from 0.7 to 14.2 kN/cm2 are preferred and pressures of from 2.8 to 10 kN/cm2 are particularly preferred.
The tablets can be cylindrical or cuboid, or else largely assume any desired geometric shapes. In the case of the cylinder, the radius to height ratio can be between 0.25 to 4. The compaction pressure can be between 12 and 0.3 kN/cm2. Preference is also given to multistage compression. Here, any desired components of the formulation are compressed in a plurality of steps one after the other, resulting in a plurality of layers. In the case of two layers, a volume ratio of the two components of from 1 to 101to 10 to 1 is preferred. This also applies mutatis mutandis for more than two layers.
The invention also provides detergent and cleaning tablets which comprise 3 to 95% of phyllosilicate/disintegrant cogranulate and 0.5 to 70% of cobuilder.
Preference is also given to detergent and cleaner tablets which comprise 3 to 95% of phyllosilicate/disintegrant cogranulate, 0.5 to 70% of cobuilder and 0.5 to 70% of additional phyllosilicate.
Preference is also given to detergent and cleaning tablets which comprise 3 to 95% of phyllosilicate/disintegrant cogranulate, 0.5 to 70% of cobuilder and 0.5 to 70% of surfactant.
Preference is also given to detergent and cleaner tablets which comprise 3 to 95% of phyllosilicate/disintegrate cogranulate, 0.5 to 70% of cobuilder, 0.5 to 70% of surfactant and 0.5 to 70% of additional phyllosilicate.
Preference is also given to detergent and cleaner tablets which comprise 3 to 95% of phyllosilicate/disintegrant cogranulate, 0.5 to 70% of cobuilder, 0.5 to 70% of surfactant and 0.5 to 70% of bleaching-active substances.
Preference is also given to detergent and cleaner tablets which comprise 3 to 95% of phyllosilicate/disintegrant cogranulate, 0.5 to 70% of cobuilder, 0.5 to 70% of surfactant, 0.5 to 70% of bleaching-active substances and 0.5 to 70% of additional phyllosilicate.
Preference is also given to detergent and cleaner tablets which comprise 3 to 95% of phyllosilicate/disintegrant cogranulate, 0.5 to 70% of cobuilder and 0.5 to 70% of bleaching-active substances.
Preference is also given to detergent and cleaner tablets which comprise 3 to 95% of phyllosilicate/disintegrant cogranulate, 0.5 to 70% of cobuilder, 0.5 to 70% of bleaching-active substances and 0.5 to 70% of additional phyllosilicate.
Preference is also given to detergent and cleaner tablets which comprise 3 to 5% of phyllosilicate/disintegrant cogranulate and 0.5 to 70% of additional hyllosilicate.
Preference is also given to detergent and cleaner tablets which comprise 3 to 5% of phyllosilicate/disintegrant cogranulate and 0.5 to 70% of surfactant.
Preference is also given to detergent and cleaner tablets which comprise 3 to 95% of phyllosilicate/disintegrant cogranulate, 0.5 to 70% of surfactant and 0.5 to 70% of additional phyllosilicate.
Preference is also given to detergent and cleaner tablets which comprise 3 to 95% of phyllosilicate/disintegrant cogranulate and 0.5 to 70% of bleaching-active substances.
Preference is also given to detergent and cleaner tablets which comprise 3 to 95% of phyllosilicate/disintegrant cogranulate, 0.5 to 70% of bleaching-active substances and 0.5 to 70% of additional phyllosilicate.
Determination of the particle size distribution using a Microtrac granulometer The particle size in the dispersion is determined using an ASVR/FRA Microtrac granulometer from Leeds and Northrup. The parameter measured is the reflection or diffraction of a laser beam upon passing through the dispersion. 400 ml of ethanol are pumped through the laser measuring cell. The solid sample (e.g. 70 mg) is automatically metered in, and after 10 min the particle size distribution is determined. The evaluation unit of the instrument calculates the d90 value.
Solubility Test
For this, 950 ml of tap water (water hardness 15 degrees of German hardness) are heat-treated at 30xc2x0 C. in a 1 l beaker and stirred with a magnetic stirrer. The detergent tablet is placed into a metal screen insert (screen size 5 mm), which in turn is immersed into the liquid. The tablet is covered by the liquid by about 2 cm. The time taken for the tablet to fall through the screen is determined as the dissolution time in seconds using a laboratory stopwatch.
Roll Compaction
In a roll compactor (Hosokawa-Bepex, model: L200/50P), the starting material is conveyed between the compactor rollers using a stuffing screw (setting: stage 2 to 3). This is done at such a rate that a laying-on length of 50 mm produces the desired compaction pressure. The roller rotation is set at stage 2 and the nip is 0.1 mm. The resulting sticks (length: about 50 mm, thickness: about 2-5 mm, width about 10-15 mm) are crushed in a hammer mill (Alpine, model UPZ) with a perforation diameter of 5 mm at a rotary speed of from 600 to 1400 rpm.
Production of Particle Size Fractions
From the crushed roll-compacted product, the coarse fraction is firstly separated off on an electrovibratory screen (Siemens) with built-in 1 mm screen. From the material which passes through the screen, the undersize fraction is separated off using a second screen (500 xcfx81m). The material which remains on the screen is the desired product.
Preparation of the Test Detergent, Procedure 1
Zeolite A/or commercially available SKS-6 powder, soda and PCA powder are thoroughly mixed in a domestic multimixer (Braun), and then the surfactants AE or MEE are sprayed on and mixed in. The other components (citric acid, hydrogencarbonate, LAS) are then mixed in. Finally, TAED, percarbonate, cellulose or phyllosilicate/cellulose cogranulate are carefully mixed in.
Preparation of the Test Detergent, Procedure 2
If required, optical brighteners are dissolved in the liquid surfactant components (AE or MEE). This solution is sprayed in a domestic multimixer (Braun) onto solid components which have been thoroughly mixed beforehand (zeolite A, phosphate, PCA, soda, hydrogencarbonate, sulfate). The other components (LAS, SAS, soap, antifoam, phosphonate, PVP, SRP, CMC) are then mixed in, Finally, TAED, perborate or percarbonate, enzymes, phyllosilicate/cellulose cogranulate are carefully mixed in.
Preparation of the Test Machine Dishwashing Detergents
The components phosphate, silicate, soda, sodium citrate and polymer were charged to a Lxc3x6dige plowshare mixer and thoroughly mixed. The alkyl ethoxylate is then sprayed on. Finally, enzymes, perfume, percarbonate or perborate, TAED and phyllosilicate/cellulose cogranulate are mixed in.
Tableting of Detergents
For tableting, the premixed test detergent is pressed to the appropriate shape using a Matra tablet press. The compaction pressure can be between 3.8 and 0.08 kN/cm2. The compact has a diameter of 41 mm and, depending on the initial weight, a height of, for example, 18 mm and a weight of, for example, 40g.
Tableting of Machine Dishwashing Detergents
For tableting, the premixed machine dishwashing detergent formulation is pressed to the appropriate shape using a Matra tableting press. The compaction pressure can be between 14.2 and 0.7 kN/cm2. The compact has a diameter of 30 mm and, depending on the initial weight, a height of, for example, 20 mm and a weight of, for example, 25 g.